Colombian President Juan Manuel Santos has announced that his government has suspended peace talks with the Farc rebel group after the suspected kidnapping of an army general.

Brig Gen Ruben Dario Alzate Mora lost contact with troops in Quibdo, southwest Colombia, an area where Farc has been known to operate.

"Tomorrow negotiators were to travel to another round of talks in Havana," Santos said.

"I will tell them not to go and that the talks are suspended until these people are released."

Santos also took to Twitter to announce the decision to suspend the negotiations which had been ongoing for two years.

"Negotiations with #Farc are suspended until the facts of the kidnapping of general (Ruben) Alzate are clarified," the Ministry of Defense said in a tweet, quoting President Santos.

"We demand that his captors (all signs point to the FARC) set him free as soon as possible, and safe and sound," Santos said on Twitter.

In reaction to the suspected kidnapping, Santos sent Defence Minister Juan Carlos Pinzon to the Choco department town of Quibdo to head the investigation.

Farc is estimated to hold around 8,000 militants who continue to wage the longest-running conflict on the Latin American continent.

In 2012, the rebels said that they would no longer kidnap civilians as part of their insurgency but said that police and soldiers would remain targets as prisoners of war.